Its smart to bring in a knowledgeable football guy for football operations. Lots of pro teams have a Team President and a GM. President looks at team from macro level- administrative overhead, legal, public relations, ticket prices, stadium deals, etc. The GM handles day to day things like salary negotiations, coaching staff changes (only top dog coaches have final say on staffing, most times a GM has final authority), and game day logistics.
When Miami ends up with the next coaching search, I would be more comfortable with Highsmith running the search than Blake James.